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Publisher's Note:This Chapter has been AMENDED by new legislation (Ord. O-202009-10-030, passed 9-15-2020). The text of the amendment will be incorporated below when the amending legislation is codified.
Notes to User
The McHenry County Stormwater Management Ordinance (this Ordinance) regulates development and substantial improvements to buildings in the floodplain throughout McHenry County, within incorporated and unincorporated areas alike. As you read through this Ordinance, you will notice that certain terms are underlined and the Ordinance uses numerous acronyms. Underlined terms are defined in Appendix 12 and acronyms are defined in Appendix 13.
Not all development is regulated by this Ordinance, but development that is regulated requires a stormwater management permit before construction is allowed to commence. Some development is regulated because of its size, such as: development that hydrologically disturbs 5,000 square feet or more; development that hydrologically disturbs 50% or more of a parcel; and development that results in an additional 20,000 square feet of impervious area since the original effective date of this Ordinance. Other development is regulated because of its location, regardless of its size. Examples include development that is located partially or completely in a flood hazard area or wetland.
The basic steps used to determine whether a particular project requires a stormwater management permit are listed below. The Permitting Flow Charts in Appendix 1 provide additional guidance. If you have any questions about this Ordinance or its applicability to a specific project, please contact the McHenry County Department of Planning and Development.
1. Determine whether your project meets the definition of development (see Appendix 12). If it does, go on to Step 2.
2. Determine whether your project is regulated development (see § 17.04.020B.). If it is, go on to Step 3.
3. Determine whether your project is exempted development (see § 17.04.020C.). If it is not, go on to Step 4.
4. Determine whether your project qualifies for a General Permit, which waives certain requirements of this Ordinance in order to streamline the permit process for specific types of routine projects (see § 17.04.030). If it does, follow the process described for that General Permit. If it does not, go on to Step 5.
5. Determine how your project is classified (see § 17.04.040A.) and then go on to Step 6.
6. Determine which Application Requirements apply (see § 17.04.050). Then go on to Step 7.
7. Determine which Performance Standards apply (see § 17.04.060). Then go on to Step 8.
8. Submit a complete stormwater management permit application to a Certified Community or to the McHenry County Department of Planning and Development, along with the required submittals.
9. Await the issuance of a stormwater management permit prior to commencing your project.
17.04.010 Introduction, authority and purpose
17.04.020 Scope of regulation
17.04.030 General permits
17.04.040 Stormwater management permit provisions
17.04.050 Application requirements
17.04.060 Performance standards
17.04.070 Variances and appeals
17.04.080 Inspections and access
17.04.090 Violation and penalty
17.04.100 Procedure and enforcement
17.04.110 Disclaimer of liability
17.04.130 Abrogation and greater restrictions
17.04.150 Appendix 1: Permitting Flowcharts
17.04.160 Appendix 2: Standard Soil Erosion and Sediment Control Notes
17.04.170 Appendix 3: Standard Drain Tile Notes
17.04.180 Appendix 4: Rainfall Depth-Duration Frequency Tables for McHenry County
17.04.190 Appendix 5: Hydrologic and Hydraulic Models and Techniques Approved by MCSC
17.04.200 Appendix 6: Detention Volume vs. Percent Impervious Chart for McHenry County
17.04.210 Appendix 7: IDNR/OWR Dam Safety Permit Flowchart
17.04.220 Appendix 8: Public Bodies of Water in McHenry County
17.04.230 Appendix 9: McHenry County Watersheds
17.04.240 Appendix 10: McHenry County Watershed Plans
17.04.250 Appendix 11: Floodplain and Floodway Maps
17.04.260 Appendix 12: Definitions
17.04.270 Appendix 13: Acronyms